Method of separately obtaining potassium chlorid and borax from certain waters



UNITED, STATES PATENT 1 OFFICE.

N OAH WBINKLE AND WALTER A. KUHNERT, OF SAN FRANCISCO, CALIFORNIA.

METHOD or snrmarnn'zlonrnmmeromssium CHLORID AND BOBAX mom CERTAIN wnrnns.

Specification of Letters Patent.

Patented Aug. 17, 1 920.

No Drawing. Original application filed Kay 22 1919, Serial No. 299,042. Divided and this application filed Iuly 14, 1919.

To all whom it may concern:

Be it known that we, NOAH WRIN'KLE and WALTER A. KUHNE T, citizens of the United States, and residents of San Franciscoflin the county of San Francisco and State of California, have invented new and useful Improvements in Methods of Separately Obtaining Potassium Chlorid and Borax from Certain lVaters, of which the following is a specification.

The present application is a division of an application, Ser. No. 299,042, filed May 22, 1919, and relates to improvements in methods of obtaining potassium chlorid and borax from certain waters which contain potassium chloridand vborax and other salts. Such waters comprise inland lakes, solutions formed by dissolving in water the salts deposited on the bottoms of dry lakes, and solutions formed by dissolving .in water salts obtained by evaporation of waters of such inland lakes. 1

Waters to which it is intended to applyour improved process, may, and many do, contain such minerals as sodium carbonate, sodium bi-carbonate, sodium sulfate, sodium chlorid, sodium borate, potassium chlorid, and other minerals. Among such waters is that from Searles lake in California, of

Also that from Owens. lake in California, of which the following is the composition:--

1%,00 8. 50%. Na so I. I NaCl 9. 06, KCl 6.00 Na,B,O 3. 60 Water 69. 92

Either with or without the preliminary removal of sodium bicarbonate by treatment of the solution with carbon'dioxid, the solution is concentrated by evaporation and thereby the proportion of potassium chlorid and borax therein is increased and at the same time some of the more insoluble salts Serial No. 810,730.

may be eliminated; or there may be obtained a mixture of crude salts by permitting the solution to cool with the deposition of crystals of potassium chlorid, borax and other salts. In this manner there has been obtained from the waters of Searles lake the following composition Na CO, 1.70% l Ta. .S O 0.44 NaCl 10.93 KCl 66. 34 Na,B,,O, 10. 91 Water -1--- 9. 66

Our method of treatment is as follows Having a solution preferably saturated at atmospheric temperature, with borax and sodium chlorid, and also containing potas-' sium chlorid, sodium carbonate and sodium sulfate, we add to the solution being treated the required amount of sodium ,hydrate, either in liquid or solid form to convert the comparatively insoluble sodium bi-borate into the extremely soluble sodium metaborate, in accordance with the following formula sium chlorid. The mother liquor is then treated with carbon dioxid, obtained from a. lime kiln, or other suitable source. This treatment results in the conversion of the sodium meta-borate to sodium bi-borate, insoluble in the solution, in accordance with the following,formula:-

After removal of the borax the mother liquor is returned tothe other liquors being similarly treated or utilized to e'ifect recovery therefrom of sodium carbonate.

We claim 2- In a process of obtaining separately potassium chlorid and borax' from certain Waters containing sodium bi-borate and potassium chlorid, adding a suflicient quantity of sodium hydrate to the solution to produce Within the solution a borate compound of 10 increased solubility.

NOAH WRINKLE. W. A. KUHNERT. 

